The disclosure relates to an electronic switch.
An electronic switch is a kind of an electrical contact switching device for supplying or shutting off current, and is installed in various industrial equipments, machines or vehicles. Such an electronic switch includes a fixed contact point and a movable contact point which selectively make contact with each other, and an electric actuator for driving the movable contact point according to an electrical signal in order to allow the fixed and movable contact points to make contact with each other or to be separated from each other.
As generally known in the art, the electric actuator includes a coil for generating electromagnetic force, a fixed core fixed in the coil, a movable core movable closely to or away from the fixed core, a movable rod which moves in connection with the movement of the movable core and to which the movable contact point is fixed, and a return spring for applying elastic force to the movable core in order to allow the movable core to move away from the fixed core.
In this case, if power is applied to the coil, the magnetic field is generated from the coil and the movable core moves toward the fixed core while overcoming the elastic force of the return spring by Fleming's left-hand rule. Thus, the movable rod moves in the same direction with the movable core, so that the movable contact point makes contact with the fixed contact point.
To the contrary, if the power applied to the coil is shut off, the movable core moves away from the fixed core due to the elastic force of the return spring. Thus, the movable rod moves in the same direction with the movable core, so that the movable contact point is separated from the fixed contact point.
According to the related art described above, the movable contract point is separated from the fixed contact point only by the elastic power of the return spring. Thus, since the fixed contact point is not rapidly separated from the fixed contact point, arc having the high temperature is generated while the fixed and movable contact points are being separated from each other, so that the fixed contact point and/or the movable contact point may be damaged.